Electromagnetic test device to predict a usable life of a vacuum interrupter in the field

ABSTRACT

An electromagnetic testing assembly to predict a usable life of an installed vacuum interrupter in the field, which can include an electromagnetic testing device connected to a flexible magnetic field coil to generate a potential in a vacuum interrupter in an installation, magnetically monitor ion flow across one or more gaps in the vacuum interrupter, and apply trend data, tube chart information, and an algorithm to predict the usable life.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority to and the benefit of U.S.Provisional Patent Application Ser. No. 61/570,247 filed on Dec. 13,2011, entitled “METHOD TO PREDICT A USABLE LIFE OF A VACUUM INTERRUPTERIN THE FIELD;” U.S. Provisional Patent Application Ser. No. 61/570,253filed on Dec. 13, 2011, entitled “ELECTROMAGNETIC TEST DEVICE TO PREDICTA USABLE LIFE OF A VACUUM INTERRUPTER IN THE FIELD;” and U.S.Provisional Patent Application Ser. No. 61/570,258 filed on Dec. 13,2011, entitled “FLEXIBLE MAGNETIC FIELD COIL FOR MEASURING IONICQUANTITY.” These references are hereby incorporated in their entirety.

FIELD

The present embodiments relate to an electromagnetic test device topredict the useful life of a vacuum interrupter while the vacuuminterrupter is installed in the field.

BACKGROUND

A need exists for a fast and reliable electromagnetic testing device totest vacuum interrupters of circuit breakers to determine the usablelife expectancy thereof without having to remove the vacuum interruptersfrom their installed positions in the field.

A need exists for an electromagnetic testing device to determine theusable life expectancy of vacuum interrupters in the field that canreduce the occurrence of electrical failures, as well as death anddestruction in the field.

A need exists for an electromagnetic testing device to test vacuuminterrupters that can avoid the introduction of X-rays into workenvironments; thereby providing safe and healthy work environments.

The present embodiments meet these needs.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description will be better understood in conjunction withthe accompanying drawings as follows:

FIG. 1 depicts an electromagnetic testing device connected to a flexiblemagnetic field coil, power supply, and an installed vacuum interrupterusing a positive engagement wire and a negative engagement wireaccording to one or more embodiments.

FIG. 2 depicts a data storage of the electromagnetic testing device incommunication with a processor according to one or more embodiments.

FIG. 3 depicts a vacuum interrupter according to one or moreembodiments.

FIG. 4 depicts the electromagnetic testing device according to one ormore embodiments.

FIGS. 5A and 5B depict detailed views of two different types of fixedinner diameter magnetic coils.

FIGS. 6A and 6B depict a diagram of the method according to one or moreembodiments.

The present embodiments are detailed below with reference to the listedFigures.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Before explaining the present apparatus in detail, it is to beunderstood that the apparatus is not limited to the particularembodiments and that it can be practiced or carried out in various ways.

Historically, air magnetic and oil interrupters were the only types ofinterrupters used on circuit breakers rated at 2.4 kilovolts (kV) orhigher, with air magnetic interrupters being used on lower voltages inthis rating, including voltages ranging from 2.4 kV to 25 kV, and withoil interrupters being most commonly used on voltages higher than 25 kV,primarily because of their ability to interrupt higher arc energies.

Air magnetic interrupters degrade somewhat each time they are openedunder load, and degrade significantly when they are interrupted underfault. Contacts can be repaired or replaced if required; however,maintenance of such circuit breakers is not always properly scheduled,which can result in failures.

In addition to maintenance issues, arc-chutes are large and heavy, andsome arc chutes are fragile and can be broken if not properly handled.

Oil interrupters are heavy and submerged in oil, such that reaching theoil interrupters for inspection is difficult. As such, oil interruptersare not always maintained as they should be.

The present embodiments relate to an electromagnetic testing device forvacuum interrupters that provides for ease of testing and maintenance ofthe vacuum interrupters, use of flexible and lightweight testingequipment and allowance for testing in the field, each of which is notavailable with prior electromagnetic testing devices for vacuuminterrupters in the field.

One or more of the present embodiments relate to a closed contactelectromagnetic testing device to predict a usable life of installedvacuum interrupters in the field, as well as to an open contactelectromagnetic testing device to predict the usable life of installedvacuum interrupters in the field.

The electromagnetic testing device can use fixed size portable magneticcoils or flexible magnetic field coil, which can be lightweight and easyto use.

In embodiments, the electromagnetic testing device can be used on vacuuminterrupters that are compact and sealed.

The electromagnetic testing device can be used on vacuum interruptersthat have short gap travel distances, such as gap travel distancesranging from about 8 mm to about 12 mm.

The electromagnetic testing device can cause less damage than otherelectromagnetic testing devices for testing vacuum interrupters.

The electromagnetic testing device can be used to create a plurality ofionic or current versus pressure curves as models of the useful life ofdifferent sized vacuum interrupters, as well as store the plurality ofionic or current versus pressure curves in a library in the datastorage.

The electromagnetic testing device can be used to create a plurality oftrend data for expected life of different vacuum interrupters usingpressure and other variables, as well as storing the trend data in atrend data library in the data storage.

The electromagnetic testing device can be used to create a tube chart,which can include different values with different points. In operation,an individual vacuum interrupter can be tested to meet criteria that aredifferent than criteria met by other individual vacuum interrupters. Assuch, a unique point value can be created for each criteria of eachindividual vacuum interrupter. The sum of the points can be placed intoa unique algorithm that can utilize the trend data in the data storageto determine life expectancy for individual vacuum interrupters.

For example, a first point value can be assigned based on a model numberand the type of the vacuum interrupter being tested. For example, a GE40A1, 12 KV, 1200 amp, 18 KA vacuum interrupter can have a high firstpoint value for reliability.

The second point value can be a point value that depends on how manyoperations the individual vacuum interrupter has been used in. Forexample, 1-100 operations on the GE 40A1 can have a second point valueof 5 points assigned to it, 101 to 1000 operations on the GE 40A1 canhave a second point value of 6 points assigned to it, 1001 to 2000operations on the GE 40A1 can have a second point value of 7 pointsassigned to it, 2001 to 3000 operations on the GE 40A1 can have a secondpoint value of 8 points assigned to it, and over 3001 operations on theGE 40A1 can have a second point value of 9 points assigned to it. Thesecond point value can vary depending upon the particular individualvacuum interrupter and the number of operations it has been used in.

A third point value can relate to an age of the individual vacuuminterrupter. For example, a 5 year old vacuum interrupter can have 5points assigned to it as the third point value, a 10 year old vacuuminterrupter can have 6 points assigned to it as the third point value, a15 year old vacuum interrupter can have 7 points assigned to it as thethird point value, a 20 year old vacuum interrupter can have 8 pointsassigned to it as the third point value, and a 25 year old vacuuminterrupter can have 9 points assigned to it as the third point value.The third point value can vary depending upon the particular individualvacuum interrupter and the age of the particular individual vacuuminterrupter.

A fourth point value can be for contact resistance and wear informationfor the individual vacuum interrupter. For example, if 30 micro Ohms aremeasured, which means 80 percent of a contact surface remains for aparticular individual vacuum interrupter, then the fourth point valuecan be 5, if 40 micro Ohms are measured, which means 60 percent of thecontact surface remains, then the fourth point value can be 6, if 50micro Ohms are measured, which means 40 percent of the contact surfaceremains, then the fourth point value can be 7, if 60 micro Ohms aremeasured, which means 20 percent of the contact surface remains, thenthe fourth point value can be 8, and if 70 micro Ohms are measured,which means 10 percent of the contact surface remains, then the fourthpoint value can be 9. The fourth point value can vary depending upon theparticular individual vacuum interrupter and the amount of Ohms measuredfor the particular individual vacuum interrupter.

A fifth point value that can be used for the calculation of lifeexpectancy of the vacuum interrupters can be based on results obtainedusing the electromagnetic testing device with a specific vacuuminterrupters.

In operation, the vacuum interrupter can rate 5 points when tested at apressure of 10×E⁻⁶, the vacuum interrupter can rate 4 points when testedat a pressure of 10×E⁻⁵, the vacuum interrupter can rate 3 points whentested at a pressure of 10×E⁻⁴, the vacuum interrupter can rate 8 pointswhen tested at a pressure of 5.0×E×10⁻³, and the vacuum interrupter canrate 9 points when tested at a pressure of 10×E⁻³.

The calculation of the life expectancy can factor in a weighting valuebased on the number of vacuum interrupters tested with similar results.For example, for 1-100 samples of a certain vacuum interrupter, theweighting value can be 1.5, for 101-200 samples the weighting value canbe 1.4, for 201-300 samples the weighting value can be 1.3, for 301-400samples the weighting value can be 1.2, for 401-500 samples theweighting value can be 1.1, and for vacuum interrupters that have hadsamples tests more than 500 times the weighting value can be 1.0.

A primary basis for the wide acceptance of vacuum interrupters isfinancial. A life span and the number of vacuum interrupters can beincreased using the electromagnetic testing device disclosed herein. Theelectromagnetic testing device can allow the life span for vacuuminterrupters to range from about five times to about ten times longer,particularly for SF-6 vacuum interrupters.

The electromagnetic testing device can include simple yet ruggedlyconstructed equipment to test the vacuum interrupters.

In operation, all of the point values can be added together to attain atotal value for the vacuum interrupter. For example, all of the pointvalues can be added together to equal 20 for a particular vacuuminterrupter with a long life expectancy. A larger total value wouldindicate a need to replace the vacuum interrupter sooner than vacuuminterrupters having a lower total value.

The total value of point values can be multiplied by the weighting valuebased on a sample size to provide a point value, and the life expectancycan be determined based on a category that the point value falls into.

If the point value is between 20 and 30, this can indicate a long lifeexpectancy and that the vacuum interrupter needs to be checked in 10years.

If the point value is between 30 and 34, this can indicate that thevacuum interrupter will need to be checked and probably replaced in 5years.

If the point value is between 35 and 44, this can indicate that thevacuum interrupter will need to be checked in 2 years and probablyreplaced in 2 years.

If the point value is over 45, this can indicate that the vacuuminterrupter is about to fail and should be replaced immediately.

The use of the weighting value can yield a better and more accurateresult. Computer instructions can be formed and/or stored in the datastorage to perform calculation of the life expectancy for each vacuuminterrupter.

The electromagnetic testing device can be connected to a flexiblemagnetic field coil to perform testing.

The electromagnetic testing device can utilize calibration information,which can be created without the electromagnetic testing device, and canbe installed for use on the electromagnetic testing device.

The calibration information can include an ionic or current versuspressure calibration curve for each model vacuum interrupter.

The calibration information can be formed by testing a specificindividual model of a vacuum interrupter, which can have a vacuumcreated therein for testing at 40 different ionic currents to determine40 different points of calculated pressure or 40 different points ofmeasured amps; thereby creating an ionic or current versus pressurecalibration curve for a specific model of vacuum interruption.

Each ionic or current versus pressure calibration curve can be inputinto a library of ionic or current versus pressure calibration curves inthe data storage connected to the processor; thereby allowing a user toselect a vacuum interrupter model and obtain the corresponding ionic orcurrent versus pressure calibration curve.

Additionally, a library of trend data can be created for each of thevacuum interrupters in the library of ionic or current versus pressurecalibration curves. The trend data can be installed in the library oftrend data in data storage associated with the processor.

The trend data can include: a vacuum pressure at a date of testingversus vacuum pressure when the vacuum interrupter was manufactured toprovide a leak rate; circuit breaker type; circuit breaker serialnumber; date of vacuum interrupter manufacture; circuit breakercondition at ambient atmosphere; circuit breaker insulation resistance;circuit breaker operating condition, such as an alkaline condition or anacidic condition; serial number of the installed vacuum interrupter;vacuum interrupter wear indication data; installed vacuum interruptercontact resistance; circuit criticality, such as a level of importanceof the circuit in the facility; manufacturer name for the installedvacuum interrupters; manufacturer part number; an approximate number ofoperations on the vacuum interrupter; circuit breaker atmosphere; orcombinations thereof.

The electromagnetic testing device can include the data storage and theprocessor for use in performing testing.

The data storage with the associated processor can be a circuit board.The library of ionic or current versus pressure calibration curves andthe library of trend data can be stored in the data storage.

Additionally, a tube chart can be installed in the data storage of theelectromagnetic testing device.

The tube chart can be formed from a plurality of tube types. Each tubetype can have a tube identifier, such as a model number or serialnumber. Each tube identifier can have a tube specific ionic or currentversus pressure calibration curve.

A flexible magnetic field coil can be connected to the electromagnetictesting device. The flexible magnetic field coil can be a loop made froma plurality of insulated copper wires.

A positive pole and a negative pole can each be connected to theflexible magnetic field coil and connected to the electromagnetictesting device; thereby allowing the electromagnetic testing device toflow a high voltage to the flexible magnetic field coil when a testprocedure is actuated.

The electromagnetic testing device can be connected to a power supply toallow the electromagnetic testing device to power the flexible magneticfield coil and to perform monitoring and calculation steps required forthe testing.

The electromagnetic testing device can also be connected using apositive engagement wire to the installed vacuum interrupter at a tubeend, and a ground engagement wire on another end. The electromagnetictesting device can then be connected to a ground.

The electromagnetic testing device can be used for testing vacuuminterrupters in the field that have three gaps. The electromagnetictesting device can allow for testing of the gaps between internalcontacts of the vacuum interrupter and a metal vapor shield of thevacuum interrupter.

The three gaps in the vacuum interrupters can include a first gapbetween a moving contact portion of a contact assembly and a fixedcontact portion of the contact assembly, a second gap between the movingcontact portion and the metal vapor shield of the vacuum interrupter,and a third gap between the fixed contact portion and the metal vaporshield.

The electromagnetic testing device can allow for simultaneous testing ofall three gaps for leak detection. The electromagnetic testing devicecan prevent explosions of the vacuum interrupters by enabling quick andcheap field detection of leaks using flexible lightweight testingequipment.

The electromagnetic testing device can be used on vacuum interruptersthat have metal vapor shields that capture metal vapor or othercontaminant particles created by metallic arcing that occurs whencontacts open. The metal vapor shield can capture or inhibit the metalvapor or contaminant particles from entering the gap between the movingcontact portion and the fixed contact portion.

The metal vapor or contaminant particles can be highly ionized, cancause thermal expansion, and can be drawn to the metal vapor shield byelectrostatic forces. When the metal vapor or contaminant particlescontact the metal vapor shield, the metal vapor or contaminant particlescan quickly solidify and adhere to the metal vapor shield, which canhelp maintain both a vacuum level inside the vacuum interrupter andefficient working of the vacuum interrupter.

The metal vapor shield can also keep an electrostatic field uniformlydistributed, both inside and outside of the vacuum interrupter, toensure a longer life for the vacuum interrupter.

The metal vapor shield can protect a ceramic body of the vacuuminterrupter from high levels of radiation during arcing andinterruption, and prevent high level arcs from directly contacting theceramic body.

Accordingly, measuring the gap between the metal vapor shield and themoving contact and the gap between the metal vapor shield and the fixedcontact can ensure proper functioning of the vacuum interrupter.Additionally, the electromagnetic testing device can be used to measurethe gap between the fixed contact portion and moving contact portion,also referred to as the primary gap.

The electromagnetic testing device can provide improved results whenhigh-potential testing is performed on the vacuum interrupter. Theelectromagnetic testing device can allow a high-potential voltage to beapplied across open contacts of the vacuum interrupter, allow thevoltage to increase to a test value, and then measure leakage ofcurrent.

The electromagnetic testing device can allow for determination of verylow quantities of current leakage for both AC high-potential tests andDC high-potential tests.

The high-potential tests can use the Penning Discharge Principle. Theelectromagnetic testing device can utilize the Penning DischargePrinciple that when a high voltage is applied to open contacts in a gasand a contact structure is surrounded with a magnetic field, an amountof current flow between plates is a function of gas pressure, appliedvoltage, and magnetic field.

The electromagnetic testing device can create a magnetic field using afield coil. The vacuum interrupter can be placed into the field coil.

The magnetic field can be created using a flexible magnetic field coil,and then applying direct current (DC) to the flexible magnetic fieldcoil. Next, a constant DC voltage, such as 10 kV, can be applied to opencontacts, and current flow through the vacuum interrupter can bemeasured with the field coil. In one or more embodiments, the DC voltagecan range from 10 volts to four thousand volts.

Since the magnetic field (D) and the applied voltage (DC) are bothknown, the only variable remaining is the pressure of the gas. If therelationship between the gas pressure and the current flow is known,then the internal pressure can be calculated based on the amount ofcurrent flow. The electromagnetic testing device can utilize thiscalculation.

One or more embodiments of the electromagnetic testing device do notgenerate X-rays during testing, in addition to providing accurate testvalues in the field using DC high-potential tests. In otherelectromagnetic testing devices, DC voltages, when applied across thegaps of the contacts, generate X-rays that are known to be harmful tooperators without protection.

As such, the electromagnetic testing device allows vacuum interruptersto be tested in the field without the need for lead-based suits byreducing the potential of harm to operators. By not generating X-raysduring testing, the electromagnetic testing device can save lives andprevent known harms to humans.

The electromagnetic testing device can be used to provide high-potentialtests and contact-resistant tests to vacuum interrupters in the field todetermine if the vacuum interrupters need to be replaced. Thehigh-potential tests and contact-resistant tests can be quicklyperformed in the field using the electromagnetic testing device, such asin less than 3 hours.

The electromagnetic testing device can allow for testing of pressureinside the vacuum interrupters. Magnetrons and associated equipment havetraditionally been used to test for pressure inside vacuum interrupters.Magnetrons and associated equipment are too bulky and heavy forefficient use in the field, are difficult to calibrate when moved, donot have trending and prediction tools for evaluating their tests, andrequire the removal of the vacuum interrupters from associated circuitbreaker mechanisms.

The electromagnetic testing device can be easily implemented by lessexperienced operators in the field without requiring removal of thevacuum interrupters from associated circuit breakers.

The electromagnetic testing device can allow for testing, prediction,and trending of vacuum interrupter failure rates in the field.

One or more embodiments can include a flexible magnetic field coil forapplying directly to the vacuum interrupter. The flexible magnetic fieldcoil can be used on an entire pole, such as when the vacuum interrupteris not readily available.

Turning now to the figures, FIG. 1 depicts an embodiment of theelectromagnetic testing device 59 having a connected body 10 and acloseable lid 11.

The electromagnetic testing device 59 can have a face plate 12.Capacitors beneath the face plate 12 can collect and release an electriccharge. Also, rectifiers, relays, and a circuit board with the processorand the data storage can be disposed beneath the face plate 12.

The face plate 12 can have a power-in plug 14 for receiving 110 volts or220 volts of AC current or another current from a power supply 93.

The capacitors beneath the face plate 12 can connect to additional plugsin the face plate 12, such as a high voltage output plug 15, a magneticcontrol positive output plug 16, and a magnetic control negative outputplug 17.

The electromagnetic testing device 59 can connect to a flexible magneticfield coil 79 through a positive magnetic control wire 78 engaging themagnetic control positive output plug 16 and a negative magnetic controlwire 77 engaging the magnetic control negative output plug 17.

In operation, upon actuation of the electromagnetic testing device 59,the electromagnetic testing device 59 can provide a current to theflexible magnetic field coil 79; thereby creating a magnetic fieldaround an installed vacuum interrupter 80.

The installed vacuum interrupter 80 can be installed at an installedlocation 84, such as a power plant's circuit breaker switch room.

The installed vacuum interrupter 80 can be connected to theelectromagnetic testing device 59 through a positive engagement wire 102and a ground engagement wire 103.

The flexible magnetic field coil 79 can be wrapped around the installedvacuum interrupter 80.

The electromagnetic testing device 59 can have a ground plug 95connecting to a ground wire 97 for grounding the electromagnetic testingdevice 59.

A test button 18 can be installed on the face plate 12 to actuatecomputer instructions in the data storage to actuate a test.

A display 85 on the face plate 12 can display calculated test results toa user.

The electromagnetic testing device 59 can be in communication with aclient device 96 through network 94 for remote monitoring and actuationof the electromagnetic testing device 59.

In operation, when a strong magnetic field is applied around the vacuuminterrupter 80, ions will move producing a current across an opencontact. This ionization current is directly proportional to a pressureinside the vacuum interrupter 80. With a known ionic or current versuspressure current curve, the pressure inside the vacuum interrupter 80can be easily determined through the Penning Discharge Principle.

FIG. 2 depicts the data storage 75 of the electromagnetic testing device59 in communication with the processor 76.

A library of ionic or current versus pressure calibration curves 50 canbe stored in the data storage 75.

A library of trend data 60 for each individual vacuum interrupter can bestored in the data storage 75.

The library of trend data 60 can include at least a vacuum interrupterserial number, a vacuum interrupter model or type, calculated pressurefrom other tests by the electromagnetic testing device testing identicalmodel vacuum interrupters, calculated amp from other tests by theelectromagnetic testing device testing identical model vacuuminterrupters, or combinations thereof. Additional trend data can bestored in the library of trend data.

A tube chart 70 of tube types 72 can be stored in the data storage 75.Each tube type can have a tube identifier 73. Each tube identifier 73can be linked to a tube specific ionic or current versus pressurecalibration curve 74 in the library of ionic or current versus pressurecalibration curves 50.

The data storage 75 can include computer instructions for measuring ioncurrent flow across one or more gaps in the vacuum interrupter 101.

The data storage 75 can include computer instructions to link one of thetube types to a selected tube type to associate an ionic or currentversus pressure calibration curve with the selected tube type 120.

The data storage 75 can include computer instructions to instruct theprocessor to apply the DC potential across the one or more gaps in theinstalled vacuum interrupter 136 a.

The data storage 75 can include computer instructions to instruct theprocessor to form a magnetic field around the installed vacuuminterrupter using the flexible magnetic field coil 136 b.

The data storage 75 can include computer instructions to instruct theprocessor to create an ion current flow across the one or more gaps ofthe installed vacuum interrupter 136 c.

The data storage 75 can include computer instructions to instruct theprocessor to measure a quantity of ions travelling across the one ormore gaps to compare ion current flow before the one or more gaps to ioncurrent flow after the one or more gaps 136 d.

The data storage 75 can include computer instructions to instruct theprocessor to calculate a pressure based on a difference in measuredquantity of ions flowing across the one or more gaps 136 e.

The data storage 75 can include computer instructions to instruct theprocessor to position the calculated difference in measured quantity ofions flowing across the one or more gaps on an ionic or current versuspressure calibration curve for the installed vacuum interrupter from thelibrary of ionic or current versus pressure calibration curves 136 f.

The data storage 75 can include computer instructions to instruct theprocessor to present the calculated pressure or calculated amps based onthe calculated pressure on a display of the electromagnetic testingdevice 136 g.

The data storage 75 can include computer instructions to calculate lifeexpectancy of the vacuum interrupter using test results and the trenddata 138.

The data storage 75 can include computer instructions to print the testresults on an installed printer integrated with the test unit 146.

FIG. 3 depicts an embodiment of a vacuum interrupter 80 with a body 106,also referred to as an insulator body. The body 106 can be made ofglass, metal, ceramic, or combinations of these materials, forming acase.

The body 106 can have one or two segments.

The vacuum interrupter 80 can have a top 114, bottom 115, and mountingmeans 116.

The vacuum interrupter 80 can have a fixed contact 107, which can bemetal, slotted, solid, or combinations thereof. The fixed contact 107can engage a fixed contact stem 110.

One or more embodiments of the vacuum interrupter 80 can have a vaporshield 108, which can be for shielding metal vapor or othercontaminants. The vapor shield 108 can collect metal that comes off ofcontacts during application of current to the contact, can stopsputtering material from contaminating the inside of the case thatoccurs, and can control flashing.

The vacuum interrupter 80 can have a moving contact 109 connected to amoving contact stem 111 surrounded by a moving contact guide 113, whichcan be made of plastic.

A bellows 112, which can be made of stainless steel, can be disposedwithin the bottom 115 between the moving contact 109 and moving contactstem 111.

In operation, the moving contact stem 111 can engage a circuit breakermotor, which is not shown.

A first gap 81 a can be formed between the moving contact 109 and thevapor shield 108, a second gap 81 b can be formed between the fixedcontact 107 and the moving contact 109, and a third gap 81 c can beformed between the fixed contact 107 and the vapor shield 108.

FIG. 4 depicts another embodiment of the electromagnetic testing device59 having a housing 19.

The face plate 12 can be disposed on the housing 19, and a circuit boardthat contains the data storage with the processor can be disposedbeneath the face plate 12. The circuit board can connect to at least onecapacitor beneath the face plate 12 for accepting power from a power inplug engaging the power supply that can be connected to the back of thehousing 19.

The power supply can provide power to the processor of theelectromagnetic testing device 59.

An on/off switch 9 can be used to turn the electromagnetic testingdevice 59 on and off.

Prior to initiating testing, a user can select a tube type, which can bedisplayed on a tube type display 20, such as by using a selector button21 that connects to the tube chart in the data storage, a number upselector 22, and a number down selector 23.

The user can also select between a single gap vacuum interrupter testand a double gap vacuum interrupter test, such as by reconnecting testleads to shield contacts or across contacts.

Additionally, the user can select, using a test selector switch 25, froma fixed magnetic field test using non-flexible canisters of magneticcoils having a fixed inner diameter and a test using the flexiblemagnetic field coil.

To initiate the testing by the electromagnetic testing device 59, a testbutton 18 can be depressed to actuate a series of computer instructionsin the data storage for powering a capacitor, discharging the capacitorinto the vacuum interrupter while powering the magnetic field, andreceiving signals from the magnetic field from a signal input wire thatengages a signal input plug 26.

Computations performed using the computer instructions can be displayedon displays in the face plate 12. For example, results can be presentedon a main pressure or amp results display 27 and an exponential factordisplay 28. Also, a unit choice can be indicated as Pascals or as Ampsusing light emitting diodes “LED” lights 29 a and 29 b.

A print button 30 can be used to actuate computer instructions in thedata storage to print test results on a built in printer 31.

In one or more embodiments, the electromagnetic testing device 59 can belightweight and usable for labs and shops. For example, theelectromagnetic testing device 59 can weigh less than ten pounds.Additionally, the electromagnetic testing device 59 can have ameasurement range from about 1×10⁻⁵ Pascals to about 1×10⁻¹ Pascals. Themeasurement accuracy can be less than 10 percent for measurements from1×10⁻⁴ Pascals and 1×10⁻¹.

In operation, the electromagnetic testing device 59 can be easy and safeto operate without causing damage to the vacuum interrupter duringtesting, and without jeopardizing the life of the user during testing.

The electromagnetic testing device 59 can also have a coil choiceselector 24 for selecting a flexible magnetic field coil.

FIGS. 5A and 5B depict details of two different types of fixed innerdiameter magnetic coils 51 a and 51 b that can be used to test vacuuminterrupters instead of using a flexible magnetic field coil.

Each fixed inner diameter magnetic coil 51 a and 51 b can have aninsulated metal housing 33 a and 33 b that has a central chamber 37 aand 37 b for receiving vacuum interrupters 80 a and 80 b.

A plurality of insulated copper wires 38 a and 38 b can be disposedaround the central chambers 37 a and 37 b in the insulated metalhousings 33 a and 33 b to create the magnetic field.

A copper plate can be on a bottom of the inside of the insulated metalhousings 33 a and 33 b for connecting to the vacuum interrupters 80 aand 80 b that have been removed from a breaker or contactor. As such, aconsistent and uniform magnetic field can be formed for accurate vacuuminterrupter condition measurements. The fixed inner diameter magneticcoils 51 a and 51 b can have various inner diameter sizes.

Each fixed inner diameter magnetic coil 51 a and 51 b can have positivemagnetic connections 34 a and 34 b and negative magnetic connections 35a and 35 b.

Each fixed inner diameter magnetic coil 51 a and 51 b can have a fixedinner diameter 32 a and 32 b.

FIGS. 6A and 6B depict an embodiment of the method.

The method can include creating and installing the library of ionic orcurrent versus pressure calibration curves for individual vacuuminterrupters in the data storage of the electromagnetic testing device,as illustrated by box 6000.

The method can include creating and installing the library of trend datafor each individual vacuum interrupter in the data storage of theelectromagnetic testing device, as illustrated by box 6002.

The method can include creating and installing the tube chart in thedata storage of the electromagnetic testing device, as illustrated bybox 6004.

The method can include placing an installed vacuum interrupter within aflexible magnetic field coil without removing the installed vacuuminterrupter from an installed location in an operating unit, asillustrated by box 6006.

The method can include using a closed circuit test and actuating a DCpotential from the electromagnetic testing device to cross the first gapin the installed vacuum interrupter between a vapor shield in theinstalled vacuum interrupter and a contact assembly in the installedvacuum interrupter, as illustrated by box 6008 a; or the method caninclude using an open circuit test and placing the DC potential acrossthe first gap and a second gap between a first contact and a secondcontact of the installed vacuum interrupter in the open positionallowing ion current flow across the first gap and second gap, asillustrated by box 6008 b.

The method can include selecting a tube type using a pressure sensitivedisplay on the electromagnetic testing device, as illustrated by box6010.

The method can include displaying the selected tube type for theinstalled vacuum interrupter on a display of the electromagnetic testingdevice, as illustrated by box 6012.

The method can include measuring ion current flow across the first gapand/or the second gap of the installed vacuum interrupter by using asignal from the flexible magnetic field coil and using computerinstructions in the data storage for measuring ion current flow, asillustrated by box 6014.

The method can include linking one of the tube types to the selectedtube type to associate an ionic or current versus pressure calibrationcurve with the selected tube type, as illustrated by box 6016.

The method can include selecting an output reading for theelectromagnetic testing device consisting of either a direct pressurereading in Pascals or an ionic current reading in amps, as illustratedby box 6018.

The method can include actuating testing by the electromagnetic testingdevice by using computer instructions in the data storage to instructthe processor to: apply the DC potential across the first gap and/or thesecond gap in the installed vacuum interrupter, form the magnetic fieldaround the installed vacuum interrupter using the flexible magneticfield coil, create the ion current flow across the first gap and/or thesecond gap of the installed vacuum interrupter, measure the quantity ofions travelling across the first gap and/or the second gap to compareion current flow before the first gap and/or the second gap to ioncurrent flow after the first gap and/or second gap, and calculate apressure based on the difference in measured quantity of ions flowingacross the first gap and/or second gap, as illustrated by box 6020.

The method can include using a closed circuit test and actuating a DCpotential from the electromagnetic testing device to cross the third gapin the installed vacuum interrupter between the vapor shield in theinstalled vacuum interrupter and the contact assembly in the installedvacuum interrupter, as illustrated by box 6022

The method can include measuring ion current flow across the third gapof the installed vacuum interrupter by using a signal from the flexiblemagnetic field coil and using computer instructions in the data storagefor measuring ion current flow, as illustrated by box 6024.

The method can include actuating testing by the electromagnetic testingdevice by using computer instructions in the data storage to instructthe processor to: apply the DC potential across the third gap in theinstalled vacuum interrupter, form the magnetic field around theinstalled vacuum interrupter using the flexible magnetic field coil,create the ion current flow across the first gap and/or the second gapof the installed vacuum interrupter, measure the quantity of ionstravelling across the third gap to compare ion current flow before thethird gap to ion current flow after the third gap, and calculate apressure based on the difference in measured quantity of ions flowingacross the third gap, as illustrated by box 6026.

The method can include determining an anticipated life expectancy of theinstalled vacuum interrupter by: positioning the calculated amp orcalculated pressure on the ionic or current versus pressure calibrationcurve for the installed vacuum interrupter and identifying the trenddata from the library of trend data corresponding to the installedvacuum interrupter and to the calculated pressure or to the calculatedamp of the installed vacuum interrupter to determine the anticipatedlife expectancy in years and months for the installed vacuuminterrupter, as illustrated by box 6028.

The method can include providing the calculated amp or calculatedpressure to an RS232 interface or a printer, as illustrated by box 6030.

The method can include using a printer that is integrated with theelectromagnetic testing device to print the calculated amp or calculatedpressure and to provide a location of the calculated amp or calculatedpressure on the ionic or current versus pressure calibration curve ofthe installed vacuum interrupter, as illustrated by box 6032.

The method can include resetting the display using a reset button on theelectromagnetic testing device to: turn off an LED light, clear thecalculated amp, clear the calculated pressure, or combinations thereof,as illustrated by box 6034.

The method can include using the LED light to indicate when theelectromagnetic testing device is performing the test, as illustrated bybox 6036.

The method can include connecting the processor with a network forcommunication to a client device remote to the processor, as illustratedby box 6038.

While these embodiments have been described with emphasis on theembodiments, it should be understood that within the scope of theappended claims, the embodiments might be practiced other than asspecifically described herein.

What is claimed is:
 1. An electromagnetic testing assembly to predict a usable life of a vacuum interrupter, the electromagnetic testing assembly comprising: a. an electromagnetic testing device connected to a flexible magnetic field coil and a power supply, wherein the electromagnetic testing device comprises: (i) a housing with a face plate; (ii) a processor disposed within the housing; (iii) a means for storing and discharging a high voltage connected to the power supply and the processor, and housed in the housing; and (iv) a data storage connected to the processor, wherein the data storage comprises:
 1. a library of ionic or current versus pressure calibration curves for individual vacuum interrupters;
 2. a library of trend data for each individual vacuum interrupter, wherein the trend data comprises: a. a vacuum interrupter serial number; b. a vacuum interrupter model or type; c. a calculated pressure from the electromagnetic testing device testing an identical vacuum interrupter; d. a calculated amp from the electromagnetic testing device testing the identical vacuum interrupter; and e. a tube chart of tube types, wherein each tube type has a tube identifier, and wherein each tube identifier has a tube specific ionic or current versus pressure calibration curve;
 3. computer instructions to link one of the tube types to a selected tube type to associate an ionic or current versus pressure calibration curve with the selected tube type;
 4. computer instructions to instruct the processor to: a. apply a DC potential across a first gap in an installed vacuum interrupter; b. form a magnetic field around the installed vacuum interrupter using the flexible magnetic field coil; c. create an ion current flow across the first gap of the installed vacuum interrupter; d. measure a quantity of ions travelling across the first gap to compare ion current flow before the first gap to ion current flow after the first gap; e. calculate a pressure based on a difference in measured quantity of ions flowing across the first gap; f. position the calculated difference in measured quantity of ions flowing across the first gap on an ionic or current versus pressure calibration curve for the installed vacuum interrupter from the library of ionic or current versus pressure calibration curves; and g. present the calculated pressure or the calculated amp based on the calculated pressure on a display of the electromagnetic testing device; and
 5. computer instructions to instruct the processor to determine an anticipated life expectancy of the installed vacuum interrupter by: a. positioning the calculated amp or the calculated pressure on the ionic or current versus pressure calibration curve for the installed vacuum interrupter; and b. identifying the trend data from the library of trend data corresponding to the installed vacuum interrupter and to the calculated pressure or the calculated amp of the installed vacuum interrupter to determine the anticipated life expectancy in years and months for the installed vacuum interrupter; b. a test button in the face plate to actuate the DC potential from the electromagnetic testing device to cross the first gap in the installed vacuum interrupter between a vapor shield in the installed vacuum interrupter and a contact assembly in the installed vacuum interrupter; c. a high voltage output plug in the face plate to engage a high voltage wire that provides a high voltage output to the installed vacuum interrupter; d. a positive magnetic control plug and a negative magnetic control plug; e. a ground plug for grounding the electromagnetic testing device; f. a negative wire for grounding the installed vacuum interrupter during testing; g. a magnetic control positive wire for engaging the positive magnetic control plug and providing a high voltage connection from the electromagnetic testing device; h. a magnetic control negative wire for providing a signal from the flexible magnetic field coil to the electromagnetic testing device; i. a tube type selector button for allowing a user to select a tube type number by pushing an up button or a down button; j. a tube display for displaying a selected tube type; k. a pressure result or an amp result display for showing the calculated pressure or the calculated amp in Pascals or amps using the library of ionic or current versus pressure calibration curves, the trend data, and the signal from the flexible magnetic field coil; and l. an on/off switch for turning on or off the electromagnetic testing device, wherein the flexible magnetic field coil is connected to the electromagnetic testing device and surround the installed vacuum interrupter with a magnetic field initiated by supplying current to the flexible magnetic field coil from the electromagnetic testing device while the electromagnetic testing device provides a high voltage current to the installed vacuum interrupter, and wherein the flexible magnetic field coil provides an ion count signal to the electromagnetic testing device for use in computing the anticipated life expectancy of the installed vacuum interrupter using the ionic or current versus pressure calibration curves, the trend data, the tube chart, and an algorithm for applying point values to a specific tested vacuum interrupter.
 2. The electromagnetic testing assembly of claim 1, further comprising an RS232 interface or a printer mounted to the housing.
 3. The electromagnetic testing assembly of claim 1, further comprising a printer integrated with the housing to print the calculated amp or the calculated pressure, and to provide a location of the calculated amp or the calculated pressure on the ionic or current versus pressure calibration curve of the installed vacuum interrupter.
 4. The electromagnetic testing assembly of claim 1, further comprising a reset button on the electromagnetic testing device to perform a member of the group consisting of: turning off an LED light, clearing the calculated amp, clearing the calculated pressure, and combinations thereof.
 5. The electromagnetic testing assembly of claim 1, further comprising an LED light to indicate when the electromagnetic testing device is performing a test.
 6. The electromagnetic testing assembly of claim 1, wherein the library of trend data further comprises a member of the group consisting of: a. a vacuum pressure at a date of testing versus a vacuum pressure when the installed vacuum interrupter was manufactured to provide a leak rate; b. a circuit breaker type; c. a circuit breaker serial number; d. a circuit breaker condition in an ambient atmosphere; e. a circuit breaker insulation resistance; f. circuit breaker operating conditions; g. a serial number of the installed vacuum interrupter; h. vacuum interrupter wear indication data; i. an installed vacuum interrupter contact resistance; j. circuit criticality; k. a manufacturer part number of the installed vacuum interrupter; l. an approximate number of operations on the installed vacuum interrupter; m. a circuit breaker atmosphere; and n. combinations thereof.
 7. The electromagnetic testing assembly of claim 1, further comprising computer instructions in the data storage to instruct the processor to: a. apply a DC potential across a second gap in the installed vacuum interrupter, wherein the second gap is between a moving contact of the contact assembly and a fixed contact of the contact assembly, and wherein the first gap is between the vapor shield and the moving contact; b. create an ion current flow across the second gap of the installed vacuum interrupter; c. measure a quantity of ions travelling across the second gap to compare ion current flow before the second gap to ion current flow after the second gap; d. calculate a pressure based on a difference in measured quantity of ions flowing across the second gap; e. position the calculated difference in measured quantity of ions flowing across the second gap on an ionic or current versus pressure calibration curve for the installed vacuum interrupter from the library of ionic or current versus pressure calibration curves; and f. present the calculated pressure or the calculated amp based on the calculated pressure on the display of the electromagnetic testing device, wherein the test button actuates the DC potential from the electromagnetic testing device to cross the second gap.
 8. The electromagnetic testing assembly of claim 7, further comprising computer instructions in the data storage computer instructions to instruct the processor to: a. apply a DC potential across a third gap in the installed vacuum interrupter, wherein the third gap is between the moving contact and the vapor shield; b. create an ion current flow across the third gap of the installed vacuum interrupter; c. measure a quantity of ions travelling across the third gap to compare ion current flow before the third gap to ion current flow after the third gap; d. calculate a pressure based on a difference in measured quantity of ions flowing across the third gap; e. position the calculated difference in measured quantity of ions flowing across the third gap on an ionic or current versus pressure calibration curve for the installed vacuum interrupter from the library of ionic or current versus pressure calibration curves; and f. present the calculated pressure or the calculated amp based on the calculated pressure on the display of the electromagnetic testing device, wherein the test button actuates the DC potential from the electromagnetic testing device to cross the third gap. 